diff options
| author | Alexey Kardashevskiy <aik@amd.com> | 2025-12-02 13:44:48 +1100 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2025-12-02 12:06:45 -0800 |
| commit | eeb934137debfbe98be61a27756a605edf492ed3 (patch) | |
| tree | ec49887940c079bc172fd59bf18e21aa58dedf0e | |
| parent | c3859de858aa7ae0d0a5ca21e8ee9792f2f256b6 (diff) | |
| download | tip-eeb934137deb.tar.gz | |
iommu/amd: Report SEV-TIO support
The SEV-TIO switch in the AMD BIOS is reported to the OS via
the IOMMU Extended Feature 2 register (EFR2), bit 1.
Add helper to parse the bit and report the feature presence.
Signed-off-by: Alexey Kardashevskiy <aik@amd.com>
Link: https://patch.msgid.link/20251202024449.542361-4-aik@amd.com
Acked-by: Joerg Roedel <joerg.roedel@amd.com>
Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| -rw-r--r-- | drivers/iommu/amd/amd_iommu_types.h | 1 | ||||
| -rw-r--r-- | drivers/iommu/amd/init.c | 9 | ||||
| -rw-r--r-- | include/linux/amd-iommu.h | 2 |
3 files changed, 12 insertions, 0 deletions
diff --git a/drivers/iommu/amd/amd_iommu_types.h b/drivers/iommu/amd/amd_iommu_types.h index a698a2e7ce2a6e..a2f72c53d3cca8 100644 --- a/drivers/iommu/amd/amd_iommu_types.h +++ b/drivers/iommu/amd/amd_iommu_types.h @@ -107,6 +107,7 @@ /* Extended Feature 2 Bits */ +#define FEATURE_SEVSNPIO_SUP BIT_ULL(1) #define FEATURE_SNPAVICSUP GENMASK_ULL(7, 5) #define FEATURE_SNPAVICSUP_GAM(x) \ (FIELD_GET(FEATURE_SNPAVICSUP, x) == 0x1) diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c index f2991c11867cba..ba95467ba492b4 100644 --- a/drivers/iommu/amd/init.c +++ b/drivers/iommu/amd/init.c @@ -2252,6 +2252,9 @@ static void print_iommu_info(void) if (check_feature(FEATURE_SNP)) pr_cont(" SNP"); + if (check_feature2(FEATURE_SEVSNPIO_SUP)) + pr_cont(" SEV-TIO"); + pr_cont("\n"); } @@ -4015,4 +4018,10 @@ int amd_iommu_snp_disable(void) return 0; } EXPORT_SYMBOL_GPL(amd_iommu_snp_disable); + +bool amd_iommu_sev_tio_supported(void) +{ + return check_feature2(FEATURE_SEVSNPIO_SUP); +} +EXPORT_SYMBOL_GPL(amd_iommu_sev_tio_supported); #endif diff --git a/include/linux/amd-iommu.h b/include/linux/amd-iommu.h index 8cced632ecd031..0f64f09d1f34ff 100644 --- a/include/linux/amd-iommu.h +++ b/include/linux/amd-iommu.h @@ -18,10 +18,12 @@ struct task_struct; struct pci_dev; extern void amd_iommu_detect(void); +extern bool amd_iommu_sev_tio_supported(void); #else /* CONFIG_AMD_IOMMU */ static inline void amd_iommu_detect(void) { } +static inline bool amd_iommu_sev_tio_supported(void) { return false; } #endif /* CONFIG_AMD_IOMMU */ |